:8sin^2a cos^2a+cos4a 1+2cos^2t-cos2t 4sin^4x+sin^2 - вопрос №406760382241222442244 от annagj200430 30.01.2020 00:54

Question

Алгебра: :8sin^2a cos^2a+cos4a 1+2cos^2t-cos2t 4sin^4x+sin^2 2x cos^4a-sin^4a

annagj200430 · Answer

1) =2· 4·Sin² a Cos² a + Cos 4a= 2Sin² 2a + 1 - 2Sin² 2a = 1
2) = 1 + 2Cos² t - (2Cos²t - 1) = 2
3) = 4·Sin^4 x + 4Sin² x Cos² x = 4Sin² x( Sin² x + Cos² x) = 4Sin² x
4)= (Cos²a - Sin² a)( Cos² a + Sin² a) = Cos 2a
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